The tip of my nose is still bright red after rhinoplasty 6 weeks ago. Is this normal? (photo)

In my experience, persistent redness of the nose six weeks following rhinoplasty is not normal and should be evaluated. It is not clear to me what is being offered by "using a needle to scrape down" the bump. So, I can't offer you much guidance there. If you are concerned and unsatisfied with the explanations you are getting from your surgeon, a second opinion from a board-certified facial plastic surgeon or plastic surgeon would be helpful. 

In my practice I use either a regime of antibiotics if I think infection r a steroid Medrol dose pack if I think this is inflammation swelling. 

The redness/purple you describe is not typical.  I would see your doctor again.  If he/she still feels this is normal,  seek a second opinion for evaluation.